Removable safety-switch.



H. F. KRANTZ.

REMOVABLE SAFETY SWITCH.

APPLICATION FILED MAR. 31. Isms.

Patented Jan. 28, 1919.

3 SHEETS-SHEET H. F. KRANTZ.

REMOVABLE SAFETY SWITCH.

awucmmn man MAR. 13!. 1915.

Patentefi Jan. 28, 12

3 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

HUBERT F. KRANTZ, OF BROOKLYN, NEW YORK, ASSIQNOR T0 KRANTZ MANUFAC- TURING COMPANY, INC., 01? BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK.

REMOVABLE SAFETY-SWITCH.

Original application filed July 31, 1915,

To all whom it may concei'n:

Be it known that I, HUBERT F. KRANTZ, a citizen of the United States, and residing at Brooklyn, in the county of Kings and State of New York, have invented a new and Improved Removable Safety-Switch, of which the following specification is a full disclosure.

This application is a division of my copending case, No. 42,956, filed July 31st, 1915, and it proposes certain improvements in switch mechanisms insuring the operation thereof against accidents while at the same time affording facilities whereby certain parts may be readily inspected and renewed.

One objectof this invention is to render available a switch mechanism in the nature of a panel board so designed and constructed that an ordinary unskilled user will be barred from access to the switch blades and the contacts therefor as well as from the replaceable fuse ele1nents,thereby not only preventing him from injuring himself but also preventing from surreptitiously substitut ing improper fuse elements while yet enabling him freely to open or close the switches.

Another object is to provide a panel board whereby the janitor of a building. or other similarly qualified person may have access to the replaceable fuse elements. but only when the circuit thcreol is dead. so that he will be unable to strikean are by withdrawing the fuse from a live circuit.

Anotheuobject is so to design the panel board that a regular inspector may have access to all parts of the device. especially so that the switch blades and their immediate operating parts may be removed as units and may be examined away from the panel board or replaced by similar units.

A still further improvement insures that the switch shall 'be in open" position and with the circuit thereof "dead before enabling the switch unit to be removed: thereby preventingthe inspector from being injured or from damaging any of the parts by opening the circuit in such a way as to draw an are.

A still further object of this invention is to devise a panel board arrangement such Specification of Letters Patent.

Patented Jan. 28, 1919.

Serial No. 42,956. Divided' and this application filed March 31, 1916. Serial No. 87,925.

that a magnetic blow-out of the spark will be insured.

Other objects will be in part obvious from the annexed drawings and in part indicated in connection therewith by the following analysis of this invention.

This invention accordingly consists in the features of construction, combination of parts and in the unique relations of the members and in the relative proportioning and disposition thereof; all as more completely outlined herein.

To enable others skilled in the art so fully to comprehend the underlying features thereof that they may embody the same by the numerous modifications in structure and relation contemplated by this invention. drawings depicting a preferred form have been annexed as a part of this disclosure, and in such drawings, like characters of reference denote corresponding parts througlr out all the. views. of which:

Figure l is a sectional plan showing one form of panel board conforming to this invention; parts being cut away to show the interior thereof. Fig. 2 is a longitudinal section through line 2-2 of Fig. 1 showing further details thereof. Fig. 3 is a side elevation partly in section of a removable switch unit suitable for employment in the panel board shown by Figs. 1 and 2. Fig. 4 is an end elevation partly in section of Fig. 3. as seen along line H thereof. Fig. 5 is a modified removable unit construction showing a somewhat different switch mechanism. also capable for use in connection with the panel board illustrated by Figs. 1 and 2. Fig. (3 is an end elevation of Fig. 5 taken partly in section as seen along line 66 thereof. Fig. 7 is a wiring diagram.

Continuing now by way of a more detailed description. A denotes a panel b'ox consisting of a suitable base board 1, side walls 2 and end walls 3. either stamped up integrally of sheet metal or built up separately of pieces of insulating material, according to preference. This panel box preferably provides severalv separate compartments. i. 0.. a gutter B for various line terminals: one or more switch compartments (1 one or more fuse compartments D; and a switch actuating compartment E which may be permanently opened or may be closed by an outer door if desired. Preferably these are separated from one another as by means of partitions 4, 5, 6, etc., and they are all separated from the outer switch controlling compartment E so that access to the interior thereof may be had but not with equal facility in each instance. That is to say, the terminal compartment B will need to be opened onlyat rather infrequent intervals, and it is, therefore, proposed to close the same by means of a lid 7 held in place by screws 8 and 9. On the other hand the fuse containing compartment D may require entry quite frequently by the janitor of the building and in this embod ment of this invention it is closed by means of a door 10 hin ed at 11 and provided with a catch 12 whereby it may be locked in place under conditions shortly to be mentioned. A handle 13 may be used for opening and closing this door.

The compartment G contains switch-operating'elements of a unitary construction and each may be removed as a unit by the in specter whenever-necessary, and to that end these parts may be held in place by ordinary screws in such a way that their removal can be easily accomplished with the proper implements. These removable units will now be described. l

A removable switch-unit is shown best; by. Figs. 2, 3 and 4 and is indicated generally by F on Fig. 2, and it comprises a; suspension plate or base l4'which is suitably configurated so that'it may be interlocked in place; as for example, by means of screws 15. This base plate provides the ultimate mounting for the switch mecha nism per 86 but preferably it does not pro-.

vide the contacts for the switch blades. In the preferred form of unit, the switch blade is of laminated construction as indicated by 16, being composed of copper strips arranged echelon so as to produce oppositely angled beveled ends, and the outer strips 17 and 18 may be of heavier construction and may carry pieces 19 which are made suflici'ently durable to endure the spark. Clamping plates 20 and 21 of suitable insulating material are secured to a swinging block 22 by means of bolts 23. I These blocks 22- have side flanges 24. which are perforated to receive a shaft 25, which in turn passes through the sides 26 of a supporting frame 27 secured to the base plate 14 by means of screws 28. Two disks 29 of'insulating inatcrial will prevent the switch blades 16 from coming into contactsidewise with the sup porting frame 26. ling the swing of the switch blade 16 will not be described. I

'An arm 30 extends radially from the swinging block 22 and is apertured to provide the internal cam indicated by 31. This The means for controlcam co-acts with a roller 32 pivoted to the end 33 of a hand lever G which is pivoted by means of a stud 34: to the side walls 26 of a supporting frame 27. This internal cam 31 is so contoured that 'when the parts arc in the position shown by Fig. 3 the move clockwise under the reaction against.

the post 35 will tend to hold or swing the lever G clockwise also; with the result that the parts will be in stable position. This represents the dead or open circuit position of the switch unit, and the advantage of this construction isthat when the unit is removed and handled when in this posi tion, it tends to remain thus set or locked, and the attendant is thus enabled to replace the unit in the same relation that it is removed.

In replacing the unit, it is only necessary to thrust the lower part thereof through ,the aperture providing admission to the against the contact piece I forming part of the branch-line electrical conductors. This immediately establishes electrical. connection between the contact terminals I and H.

It maybe noted that as the handle 40 enters its final position when turned anticlockwise the blade will be sprung against these contacts and held in that position by ,'means of the peculiar contour of the-cam at the point 41; or conversely as already explained. The effect of this is not only to lock the switch blades firmly against their electrical contacts but also to insure a quick break when the handle 40 is swung clockwise to open the circuit. The quick break effect is preferably further accentuated. by

means of-a magnetic blow-out as follows:

The conductor I is connected by means of a copper strip l2 with the ribbon or wire 43 forming the winding of an clcctromagnet J which has its core or armature it connected with pole pieces 45 which terminate at -the arcing region of the terminal I. By this arrangement a magnetic field is set up across the path of movement of the switch blade 16 so that when'the circuit is broken the arc-Will be blownout magnetically.

not be lifted u a for a similar reason. This p from its effective The terminal I delivers its current through the intermediary of a conductor 46 (which is connected with the clip 47) to the fuse K. A similar clip 48 at the other end of the fuse provides a path for the flow of the current to othe connections or terminals as may be desired.

Reverting now to the switch unit, it is to be noted that a. movable tongue L is so positioned during the actuation of the switch as to control the opening of the door 10,'and preferably also to prevent the removal of the switch unit. In this instance this is accomplished by pivoting the tongue L at 50 to the link G and providing it with a slideway 51 cooperating with the stud 52 so that the tongue L will be withdrawn or retracted osition when the switch is set into its dea position; and so that it will be projected into its effective position when the switch has been moved or set into its live position. That is to say, when the switch is dead the tongue L will be in the position shown by Fig. 2; but when the switch is turned on the tongue L will project underneath the part 38, and will thus prevent the baseboard 14 from being lifted up-and away from said part; even though the screw 15 be removed. When the switch is in this position. the blade 16 will also bear against the normally liveterminal H in such a way that the other end of the base 14 canconstruction, t erefore, prevents the switch from being removed when it is in live position.

The means locking the door to the fuse compartment will now be described. A spring latch M is mounted on the cross piece 53 in such a manner that it may slide back and forth and this latch terminates in a head 54 which is beveled and which may enter the adjacent aperture or socket 12 in a catch depending from the door 10 and thus prevent the door from being opened. lormally a spring 55 presses against the head 56 and holds the'latch 54 in the position shown by Fig. 2. but when the switch is closed the tongue L will project against the head 56 and urge the latch 54: into'a. position preventing any opening of the door 10,

The switch shown by Figs. 3 and 4 is of such a construction that springs may be dispensed with entirely, if desired, because the parts may be held in either one of their two extreme positions through pressures derived from the resilient switch blade 16, which, in its one position is sprung against the circuit contacts, and in its other position is sprung againstthe post 35. At the same time this switch provides a suflioiently quick break for all practical purposes. especially in cooperation with the magnetic blow-out. Tn case a mechanically quicker switch should be desired, thls unit may be interchanged by the spring actuated unit set forth in and 6.

The detachable spring actuated switch mechanism shown by Fi s. 5 and 6 may be successfully used for al purposes with a Figs. 5

'magnetic blow-out, and for even most purposes without a magnetic blow-out. This unit comprises a frame denoted generally by thecharacter N, and which may be built of a number of parts, as for example, the face plate 60 of insulating material and the metallic side flanges 61 connected thereto by means of the plate 62 and the screws 63. This face plate 60 is in turn contoured to interfit with the opening provided by the stationary supporting part or parts (is, which correspond with the parts 37 and 38 of Fig. 1; screws 65, or other conventional means,

being used to retain these elements together temporarily. The faceinplate 60 is here formed with two segmental lips 55, supported by a slot 67 through which the shank 68 of an operating handle 0 emerges. This shank terminates at the exposed side of the face plate 60 in a suitable hand grip 69 whereby the switch mechanism may be 0 erated, as will be understood. This shan is preferably pivoted about the shaft :2: which constitutes the fixed or stationary pivot of a toggle which is broken and'closed by the handle 0.

The other main operative elements are the non-floating swinging links P P, the floating lings Q Q, the swinging blade carrier R and the switch blade S. The links P and Q constitute a toggle which, when broken, permits erected toggle is arranged to hold the bladefiexed against the contacts, and a hand-opcr ated lever providing suificient lost motion to avoid hindrance is available to break the toggle and to erect the same. Thus, the lever O is pivoted to the stud :r and provides two contact surfaces 70 and 71, the one or the other of which may be brought against some other art associated with the toggle to erect or to reak it as the case may be. These surfaces 7 0 and 71 are so spaced as to provide sufficient lost motion to permit the handle 69 to move ineffectively through the major portion of its breaking stroke before the surface 70 will impact the toggle proper and so that only aslight continued movement is necessary to break the toggle.

'. the switch blade.

5 at the beginning of its breaking stroke and in full lines at the end of its breaking stroke.

As shown by Fig. 5, therefore, the lever O in full lines is ready to be'swung back to erect the toggle and close the circuit. When the lever O is thus returned, the finger or contact portion 71 thereof bears against the rounded end of the floating link Q, and

swings the links P and Q into the dotted line positions. The links P and P in this form are arranged at either side of the links Q and Q, and the links P and P are contoured to provide stop portion 74 and 75 adapted to limit the swing of theparts; the

portion 75 being arranged to be arrested by impact with a suitable part immediately after the axis W of the toggle has crossed its dead center and thus prevent any over-swing thereof. The floating link Q, is pivoted at one end to the axis w and its other'end is in any suitable manner connected to swing In this form, this is achieved, by mounting the brush of a suitable cradleor other member R mounted to provide the necessary movement as, by means ofbeing pivoted to the side 4). This cradle R is preferably made of sheet metal bent up in a U-shape and the links Q, and Q, pass between the side walls of this cradle, and are connected to the shaft .2 which is secured between said. side walls and'which constitutes a floating pivot of the toggle. A rather strong spring 7 6 has one end connected with a stud 77 on the stationary frame piece 61, and this other end bears against the cradle B So as strongly to urge the same into its open circuit position and to be efiective to do so whenever the toggle is broken. A

. sprin 73 may in'like manner bear against a pin 2 on the lever O as to lightly hold the lever in the dotted position when the toggle is unbroken. The switch blade S is preferably constructed and mountedon the cradle R in the same manner as pointed out in connection with Fig. 3, and need not; therefore, be further described.

Without further analysis, the foregoing will so fully reveal the gist of this invention.

that others can by applying current knowledge readily adapt it for various applications without omitting certain features that from the standpoint of the prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention, and therefore such adaptations should and are intended to be comprehended within the claim as new and desire to secure the following combinations of elements, oirequivalents conductor practically inaccessibly located under said overhanging ledge.

2. A safety panel combining a box; a cover displaceably carried thereby; a switch mechanism carried by said cover and displaceable therewith; a branch-line terminal in said box; a fixed cover adjacent the displaceable cover; and a live conductor terminatin near and beneath said fixed cover.

3. n inclosed switch mechanism of the nature disclosed, combining a housing providing a compartment within which a switch blade may operate; conductors supported by said housing; a unitary switch mechanism detachably mounted by said housing and having its switch blade adapted to be actuated externally of said compartment; means for detachably retaining said switch mechanism whereby the same may be removed as a unit; and a stationary main-line terminal so mountedin said housing as to be practically inaccessible when said switch unit has been removed.

4. A switch unit of the nature disclosed combining a frame adapting said unit to be detachably secured to a suitable support; a swit h blade pivoted to said frame at one side of the normally exposed face thereof; blade operating mechanism also carried by said frame at the normally unexposed side thereof; an operating handle for said mechanism located at the normally exposed side of said frame and extending therethrough into operative relation with said-mechanism;

and a stationary main-line terminal so mounted as to be practically inaccessible when said switch unit has been removed.

5. An electrical switch mechanism combining ahousin'g having a switch containing compartment; a conductor terminating in a contact piece within said compartment; a magnet in circuit with said conductor and having pole pieces adjacent said contact; and la removable switch unit separately mounted by said housing and providing a suitclrbladc; the construction being such that the-spark will be magnetically blown out in the event of the operation or removal of said unit.

(LA switch mechanism combining a stationary base having an elevated overhanging lip; an elevated'terminal closely underlying said lip so as to be practically'inaccessible to the hands; a main cove? adapted t0 fin Witness whereof, I hereunto subscribe be secured to said base; and a switsh mechamay name, as attested by the two subscribnism depending from. said main cover so as ing Witnesses. to be removable as a unit, said mechanism I HUBERT F. KRANTZ. v provided with a switch blade adaptefil to Witnesses:

reach under said 11p into contact Wits saifi J. A. NEWTON, I

terminal. S. L. WHEEL GK.

fiopies at this patent may be obtaine ier five cams each,

ari'mssiag the Commluiomr of hteits. Washisagtm, 

